The threshold is before VAT
UK delivery is free over £50 ex VAT. A basket of removal cartons, tape and paper is counted once. An order under that figure still leaves. It is not held back.
What “free” does not change
Free delivery does not move the 3pm cutoff, and it does not turn a removal carton into a Royal Mail small parcel. The small parcel maximum we publish is 450 x 350 x 160 mm on the outside. Removal cartons are for a van.